Pop!_OS uses kernelstub to manage the boot parameters and kernel images, instead of GRUB.
Follow the commands below to disable boot splash screen and show the boot verbose on:
sudo kernelstub --print-config
andy@ws:~$ sudo kernelstub --print-config
[sudo] password for andy:
Tired of pressing Command + V every time your Mac boot just to see what's running behind the Apple logo?
We can add a boot argument to NVRAM to make our Mac boot with verbose boot enabled permanently.
This is a very safe operation, and can be undone completely just like the original was...
Prefer to see what’s actually happening in the background when your CentOS Linux is booting up?
Edit /etc/default/grub with your favourite editor, such as nano or vi.
[andy@av ~]# cat /etc/default/grub
GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)"...
Prefer to see what’s actually happening in the background when Ubuntu Desktop Linux booting up?
Wait for Ubuntu to boot, then login and start a Terminal application
Edit /etc/default/grub as root, for example: sudo nano /etc/default/grub
Remove splash from GRUB_CMDLINE_LINUX_DEFAULT